A typical LCD includes a plurality of ICs (integrated circuits) and an FPC (flexible printed circuit). The ICs are used for operating the LCD, and the FPC interconnects various electronic components and elements of the LCD. Nowadays, it is customary for the ICs and the FPC to be directly bonded onto a main substrate of the LCD via an ACF (anisotropic conductive film). Generally, bonding regions are pre-formed at the substrate, and a part of each of the bonding regions is electrically connected with one or more metal conducting wires.
Referring to FIG. 3, a typical substrate 10 of a liquid crystal display includes a plurality of driving IC bonding regions 11, a plurality of FPC bonding regions 12, and a plurality of metal conducting wires 13. The driving IC bonding regions 11 are used to bond one or more driving ICs thereat, and the FPC bonding regions 12 are used to bond an FPC thereat. Each of the driving IC bonding regions 11 is electrically coupled to a corresponding FPC bonding region 12 by a corresponding wire 13. A section of the wire 13 adjacent to the FPC bonding region 12 is trapezoidal-shaped, and tapers from the FPC bonding region 12 toward the driving IC bonding region 11. A section of the wire 13 adjacent to the driving IC bonding region 11 is rectangular, and has a uniform width. Any transverse width of the trapezoidal-shaped section of the wire 13 is greater than the width of the rectangular section of the wire 13. A joint portion 131 is defined where the trapezoidal-shaped section of the wire 13 meets the rectangular section of the wire 13.
When electrostatic discharge (ESD) occurs in the liquid crystal display, electric charges are liable to transfer between the FPC bonding regions 12 and corresponding driving IC bonding regions 11 via the wires 13. The joint portions 131 interconnecting the trapezoidal-shaped sections and the rectangular sections of the wires 13 are the equivalent of electrical path resistive “bottlenecks”. That is, when electric charges transfer from the trapezoidal-shaped sections to the rectangular sections, the electric charges are prone to concentrate at the joint portions 131. When this happens, the wires 13 are liable to burn out and break the corresponding circuits. Therefore, the liquid crystal display with the substrate 10 may have poor reliability.
Accordingly, what is needed is a liquid crystal display that can overcome the above-described deficiencies.